Method and apparatus for controlling a skin texture surface on a device using a shape memory alloy

ABSTRACT

A portable electronic device ( 100 ) includes a controllable skin texture surface that includes a skin texture surface actuation structure having a plurality of hinged elements ( 802 - 808 ) with a shape memory alloy ( 812 ) coupled thereto to effect movement of the hinged elements and a flexible skin structure ( 320 ) to change a tactile configuration of at least a portion of the controllable skin texture surface. A method also includes controlling a first shape memory alloy to actuate a plurality of hinged elements and in response, controlling a second shape memory alloy to actuate a hinged lock structure to lock a plurality of hinged elements in a first position. The method also includes deactivating the first shape memory alloy and unlocking the plurality of hinged elements by actuating the first shape memory alloy to allow the hinged lock to disengage. Corresponding structure is also disclosed. The electronic device may include a passive or active shape memory alloy based hinged locking structure to facilitate a bi-stable texture element actuation configuration.

RELATED CO-PENDING APPLICATIONS

This application is related to co-pending applications entitled “METHODAND APPARATUS FOR CONTROLLING A SKIN TEXTURE SURFACE ON A DEVICE”, filedon even date, having docket number 33692.07.1607, inventor Michael E.Caine, owned by instant Assignee and is incorporated herein byreference; “METHOD AND APPARATUS FOR CONTROLLING A SKIN TEXTURE SURFACEON A DEVICE USING HYDRAULIC CONTROL”, filed on even date, having docketnumber 33692.07.3109, inventor Michael E. Caine, owned by instantAssignee and is incorporated herein by reference; and “METHOD ANDAPPARATUS FOR CONTROLLING A SKIN TEXTURE SURFACE ON A DEVICE USING AGAS”, filed on even date, having docket number 33692.07.3110, inventorMichael E. Caine, owned by instant Assignee and is incorporated hereinby reference.

FIELD OF THE INVENTION

The disclosure relates generally to portable electronic devices and moreparticularly to portable electronic devices that employ variable skintexture surfaces.

BACKGROUND OF THE INVENTION

Portable electronic devices, such as laptops, wireless handheld devicessuch as cell phones, digital music players, palm computing devices, orany other suitable devices are increasingly becoming widespread.Improved usability of such devices can increase sales for sellers asconsumer demand can be driven by differing device usabilitycharacteristics and device features.

Providing differing device usability such as by changing the tactileconfiguration and/or visual appearance of a surface of a portableelectronic device by altering the emission reflection of light to changethe overall color or graphics that appear and disappear are known.Surfaces of electronic devices, including portable electronic devicesmay include, for example, exterior surfaces of the device, activationkeys such as keys in a keypad or navigation keys, tactile navigationinterfaces, or any other suitable surface.

Also, as one example to enhance the tactile configuration and/or visualappearance of a device, it has been proposed to employ haptics such asin the form of electro-active polymers that change 3D shape, alsoreferred to as texture, based on the application of a voltage toportions of the electro-active polymer. Differing textures and shapescan thereby be produced to give the device a different visual appearanceand/or tactile configuration. For example, if a portable device includessuch electro-active polymers as a type of outer skin, turning power onto the device can cause the electro-active polymer to be activated sothat a 3D texture is present and can be felt by a user of the device. Ithas also been proposed to use piezoelectric actuators as a type ofhaptic sensor on handheld devices. In one example, a control slider isconfigured as a bending piezo-actuator. Also it has been proposed toprovide handheld devices with menus, such as piezo-actuated hapticicons, that have different tactile feedback for a user so that the usercan, for example, turn a phone to a “silent” mode from an active mode byfeeling the proper control key and receiving feedback of actuation ofthe key once it is activated. It is desirable to provide differingmethods and apparatus for actuating skin texture surfaces of a deviceand differing user experiences.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention and the corresponding advantages and featuresprovided thereby will be best understood and appreciated upon review ofthe following detailed description of the invention, taken inconjunction with the following drawings, where like numerals representlike elements, in which:

FIG. 1 is a perspective view of an example of a wireless handheld devicethat employs a controllable skin texture surface in accordance with oneembodiment of the invention;

FIG. 2 is a block diagram illustrating one example of an apparatus thatincludes control logic that controls a controllable skin texture surfacein accordance with one embodiment of the invention;

FIG. 3 is an assembly view of a portion of an apparatus in accordancewith one embodiment of the invention;

FIG. 4 is a perspective view illustrating one example of a portion of amechanical actuation structure that may be part of a controllable skintexture surface in accordance with one embodiment of the invention;

FIG. 5 is a perspective and side view of the structure shown in FIG. 4and a portion of a flexible skin structure in accordance with oneembodiment of the invention;

FIG. 6 is a cross-sectional view illustrating another example of acontrollable skin texture surface that employs a mechanical actuationstructure in accordance with one embodiment of the invention;

FIG. 7 is a cross-section view as shown in FIG. 6 with texture actuationin accordance with one disclosed example;

FIG. 8 is a top view of one example of a shape memory alloy actuationstructure that may be employed as part of a controllable skin texturesurface according to one example of the invention;

FIGS. 9 and 10 a are cross-sectional views illustrating the operation ofthe structure shown in FIG. 8;

FIG. 10 b is a diagram illustrating one example of a bi-stable shapememory alloy actuation scheme according to one example of the invention;

FIG. 11 is a top view illustrating a portion of a portable electronicdevice that employs an embodiment of a controllable skin texturesurface;

FIGS. 12 and 13 are cross sectional views of portions of FIG. 11illustrating a deactuated and actuated skin texture structure inaccordance with one embodiment;

FIG. 14 is a top view illustrating a portion of a portable electronicdevice that employs an embodiment of a controllable skin texturesurface;

FIG. 15 is a perspective view of a portable electronic device with acontrollable skin texture surface in accordance with one embodiment;

FIG. 16 is a perspective view illustrating one example of a flexibleskin structure and corresponding portion of a hydraulic actuationstructure in accordance with one example set forth in disclosure;

FIG. 17 is a block diagram illustrating the portion of a portableelectronic device in accordance with one example;

FIGS. 18 a and 18 b illustrate a cross sectional view of an embodimentemploying a flexible sliding plate in accordance with one embodiment ofthe invention;

FIGS. 19 and 20 illustrate cross sectional views of another example of agas expandable actuation structure and flexible skin structure inaccordance with one example;

FIGS. 21 and 22 illustrate a perspective view of a portable electronicdevice with a deactuated and actuated controllable skin texture surface;and

FIGS. 23-25 illustrate a perspective view of a portable electronicdevice illustrating different portions of a controllable skin texturebeing actuated and deactuated in accordance with one example disclosedbelow.

DETAILED DESCRIPTION OF THE EMBODIMENTS

Briefly, in one example, a portable electronic device includes acontrollable skin texture surface that includes a skin texture surfaceactuation structure having a plurality of hinged elements with a shapememory alloy coupled thereto to effect movement of the hinged elementsand a flexible skin structure to change a tactile configuration of atleast a portion of the controllable skin texture surface. A method alsoincludes controlling a first shape memory alloy to actuate a pluralityof hinged elements and in response, controlling a second shape memoryalloy to actuate a hinged lock structure to lock a plurality of hingedelements in a first position. The method also includes deactivating thefirst shape memory alloy and unlocking the plurality of hinged elementsby actuating the first shape memory alloy to allow the hinged lock todisengage. Corresponding structure is also disclosed. The electronicdevice may include a passive or active shape memory alloy based hingedlocking structure to facilitate a bi-stable texture element actuationconfiguration.

In another example, a portable electronic device includes a controllableskin texture surface and control logic that is operative to change atactile configuration of at least a portion of the controllable skintexture surface in response to at least any one (i.e., one or more) of:a received wireless signal, a battery level change condition, anincoming call or message, information from a proximity sensor, soundsensor, light sensor, accelerometer or other sensor that measuresenvironmental conditions, data representing a user of the device, ordata representing completion of a user authentication sequence. Theportion of the controllable skin texture surface may be part of anon-user interface portion or a user interface portion, such as afunction key, keypad or other operational element of the device.

The controllable skin texture surface may include a mechanical actuationstructure that is coupled to a flexible skin texture, such as apolyurethane layer, rubber composite or any other suitable material thatmoves in response to moving of the mechanical actuation structure. Theflexible skin structure may be affixed to a substrate including aportion of a device housing or any other suitable surface and may beformed by separate pieces or a unitary piece. The controllable skintexture surface may include a hydraulic actuation structure that iscoupled to the flexible skin structure that moves in response tomovement of fluid in the hydraulic actuation structure. In anotherexample, the controllable skin texture surface may include an expandablegas actuation structure that is operatively coupled to a flexible skinstructure that moves in response to movement of gas in the expandablegas actuation structure. Also if desired, the controllable skin texturesurface may include a shape memory alloy actuation structure that isoperatively coupled to a flexible skin structure that moves in responseto movement of a metal alloy in the shape memory alloy actuationstructure. Any desired combination of these different structures mayalso be used. The controllable skin texture surfaces include a flexibleskin structure that is raised or lowered to provide, for example, araised feature (e.g., one or more skin texture elements) that can betactically detected by a user or visually detected by a user if desired.Touch sensors, such as capacitive elements, dome key switches or othersuitable elements may be used to detect when a user touches portions ofthe flexible surface such as non-raised or raised features, tocorrespond, for example, to a button press or similar functional inputfrom the user or to actuate the controllable skin texture. It is alsopossible to place contact switches, such as dome-type switches known inthe art, below the flexible skin structure so as to be actuated by thepush of a user's finger.

In one example, the controllable skin texture surface is controlled tocause the controllable skin texture surface on the device to pulsate orotherwise change in a time-varying manner. In addition, other visualeffects may be employed including providing lighting in addition to skintexture surface control to illuminate portions of the skin texturedifferently in response to different control conditions.

In one example, a portable electronic device employs a controllable skintexture surface that includes a mechanical skin texture surfaceactuation structure that includes a sliding element operative to causemovement of portions of the flexible skin structure. In one example, thesliding element is a movable ramp structure. The flexible skin structuremoves in response to movement of the movable ramp structure to change atactile configuration of at least a portion of the controllable skintexture surface. In another example, the sliding element is a flatflexible sliding element. The skin structure moves in response tomovement of the sliding element to change a tactile configuration of atleast a portion of the controllable skin texture surface.

In one example, the movable ramp structure includes a plurality of rampseither on a single plate or on multiple moving plates. A cam or rack &pinion structure may be linked with the plurality of ramps andcontrolled either electronically or mechanically, to move at least oneof the plurality of ramps in response to an electronic control signal ormechanical movement of a portion of the device. Mechanical movement of aportion of the device may include by way of example, the moving of aflip portion of a flip phone or the cover of a laptop device. In anotherexample, the movable ramp structure includes wedge shaped elements and amovable ramp structure that engages with the wedge shaped elements suchthat movement of the ramp structure causes movement of the wedge shapedelements and movement of the flexible skin texture to produce raised (orlowered) skin texture portions as the ramps are moved. A handheldwireless device is also disclosed that employs the above structures andalso includes, a wireless telephone subsystem, display, and otherconventional electronics and functionality in addition to thecontrollable skin texture surfaces described herein.

FIG. 1 illustrates one example of a portable electronic device 100,shown in this example to be a handheld wireless device, that includes awireless telephone subsystem for communication via one or more suitablewireless networks, and other conventional circuitry along with a display102 for displaying information to a user that is coupled to the wirelesstelephone subsystem as known in the art. The portable electronic device100 also includes a controllable skin texture surface 104 that in thisexample, covers a portion of a housing (e.g., base housing) of thedevice 100 that forms part of a user interface portion, namely a userkeypad. The controllable skin texture surface 104 also includes othercontrollable surfaces 106 and 108 that are for aesthetic purposes andare controlled to change the tactile configuration of a non-userinterface portion of the portable electronic device, such as anotherarea of the outer portion of the device. As shown in this particularexample, the portable electronic device 100 is a flip phone having afoldable housing portion 110 that pivots about a pivot mechanism 112 asknown in the art. The foldable housing portion 110 may also include akeypad and controllable skin texture surface as desired. Thecontrollable skin texture surface 104 is controlled to change thetactile configuration of a portion of the skin texture surface to, inthis example, raise respective portions of the skin texture to provide atactilely detectable keypad and other tactile and/or aesthetic features.In one example, the controllable skin texture surface 104 may be flatwhen, for example, the phone is in a standby mode, but the controllableskin texture surface 104 is controlled to activate portions thereof toprovide raised keys for a keypad when an incoming wireless call isdetected and is controlled to become flat (deactivated) when a callends. Other input information is also used to control theactuation/deactuation of the controllable skin texture as describedbelow.

FIG. 2 illustrates in block diagram form the portable electronic deviceof FIG. 1 or any other suitable portable electronic device such as alaptop computer, portable Internet appliance, portable digital mediaplayer, or any other suitable portable electronic device. As shown,control logic 200 changes a tactile configuration of a portion of thecontrollable skin texture surface 104 (and/or 106 and 108) by producingcontrol information 204 (e.g., digital or analog signals) in response toat least any one of a received wireless signal, a battery level changecondition such as a low battery condition, based on an incoming call ormessage, based on information from a proximity sensor, sound sensor,light sensor or other environmental sensor generally designated as 202,or data representing a user of the device, such as the input via amicrophone and a voice recognition module that recognizes the user'svoice, or a password or passcode entered by a user indicating aparticular user, or data representing completion of a userauthentication sequence such as the entry of a password and PIN or anyother suitable authentication process as desired. Other data may also beused such as control data based on a pressure sensor, humidity sensor,shock sensor or vibration sensor. State changes may also be used tocontrol the texture such as, but not limited to, radio signal strength,device orientation, device configuration (e.g., flip open, phone modevs. audio playback mode vs. camera mode), a grip of a user or datarepresenting a change of state of a program executing on a device,including the state of a program executing on another device connectedvia a wired or wireless connection such as a server or another portabledevice. Other incoming data representing other incoming signals mayinclude, for example, changing or controlling the texture based on anincoming SMS, email or instant message, a proximity to a radio sourcesuch as an RFID reader, a Bluetooth™ enabled device, a WIFI accesspoint, or response from an outgoing signal such as a tag associated withan RFID. Other data that may be suitable for triggering or controllingthe activation of the texture may include data representing thecompletion of a financial transaction, completion of a user initiatedaction such as sending a message, downloading a file or answering orending a call, based on a timeout period, based on the location of thedevice relative to some other device or an absolute location such as aGPS location, status of another user such as the online presence ofanother instant message user, availability of a data source such as abroadcast TV program or information in a program guide, based on gameconditions such as a game that is being played on the device or anothernetworked device, based on for example, other modes of data being outputby the device such as the beat of music, patterns on a screen, actionsin a game, lighting of a keypad, haptic output, or other suitable data.By way of example, the control logic 200 may raise portions of thecontrollable skin texture surface 104 to represent keys, in response tosensor output information 206 such as the sensor 202 detecting thepresence of a user, based on a sound level detected in the room, oroutput based on the amount of light in a room.

For example, if the light level in a room decreases to a desired levelas sensed by a light sensor, the sensor 202 outputs the sensor outputinformation 206 and the control logic 200 may activate the controllableskin texture surface 104 to provide a raised keypad feature so that theuser can feel the keypad surface in a dark room since there is not muchlight to see the keypad. In addition if desired, light source(s) such asLEDs located underneath the controllable skin texture surface may alsobe illuminated under control of the control logic in response to thelight sensor detecting a low light level in the vicinity of the device.A sound sensor may also be used, for example, to control which portionsof the controllable skin texture surface are used depending upon, forexample, the amount of noise in a room. In addition, the control logic200 may control the controllable skin texture surface 104, 106 or 108 toprovide a pulsating action, or any other suitable tactile configurationas desired based on the sensor output information. For example, thedevice of FIG. 1 may have controllable skin texture surface 104configured about the exterior of the device so that when the skintexture surface is activated (e.g., raised) in certain portions, thedevice appears to be pulsating, like a heartbeat, or may provide asequential raising and lowering of certain portions of the skin textureto provide a user desired movement, such as an animated pattern.

The control logic 200 may be implemented in any suitable mannerincluding a processor executing software module that is stored in astorage medium such as RAM, ROM or any other suitable storage mediumwhich stores executable instructions that when executed, cause one ormore processors to operate as described herein. Alternatively, thecontrol logic as described herein, may be implemented as discrete logicincluding, but not limited to, state machines, application specificintegrated circuits, or any suitable combination of hardware, softwareor firmware.

In one example, the controllable skin texture surface 104, 106, and 108may include a mechanical actuation structure that is coupled to aflexible skin structure that moves in response to moving of themechanical actuation structure, a hydraulic actuation structure that iscoupled to a flexible skin structure that moves in response to movementof fluid in the hydraulic actuation structure, and expandable gasactuation structure that is coupled to a flexible skin structure thatmoves in response to movement of gas in the expandable gas actuationstructure and a shape memory alloy actuation structure that is coupledto a flexible skin structure that moves in response to movement of ametal alloy in the shape memory alloy actuation structure, or anysuitable combination thereof.

FIGS. 3-7 illustrate various examples of a mechanical actuationstructure that is used to move a flexible skin structure in response tothe moving of the mechanical actuation structure. Referring to FIG. 3, aportable electronic device 300, is shown, which may be any suitableportable electronic device as desired. The particulars of the devicedepend on the desired application. In this example, the portableelectronic device 300 includes a housing 302 with a recessed area 304that receives one or more movable ramp structures 306 or 308. Rampstructure 306 as shown here includes a single plate that has a pluralityof ramp portions 310 that are raised with respect to the plate. Theplate slidably moves in the recessed area 304 and is allowed to slideback and forth in the recessed area. As recognized, any suitableconfiguration may be used to provide the sliding operation. The plate ismoved by an actuator 312 such as a cam or motor or any combinationthereof or any other suitable structure. The controllable skin texturesurface includes a flexible skin structure 320 that, in this example,includes molded texture elements that may be any suitable shape andsize, shown in this example as texture pockets generally shown as 322 inthe configuration of a keypad. The texture pockets 322 are molded aspockets in an under portion of the flexible skin structure 320 and areraised up by corresponding ramps 310 on the ramp structure 306 when theramp structure is moved. Hence, the texture pockets 322 are raised undercontrol of the actuator 312. The flexible skin structure covers theramps and may be affixed to the housing or other structure as desired.It will be recognized that one ramp may be used to move multiple textureelements and that the ramps may also be any suitable configuration(including shape or size).

The flexible skin structure 320 may be made out of any suitable flexiblematerial including, but not limited to polyurethane, rubber, orsilicone. It may be suitably attached to an outer portion of the housingof the device 300 via an adhesive or any other suitable mechanism. Theflexible skin structure 320 as shown has a portion that covers themovable ramp structure 306. When the movable ramp structure 306 pushesup the molded pockets 322, it changes the tactile configuration of thecontrollable skin texture surface so a user will feel the locationsbelow the ramps on the flexible skin structure 320. As shown, there maybe touch sensors 324, shown as capacitive sensors positioned on the rampstructure 306 at locations between the ramps if desired, or on top ofthe ramps if desired which when touched by a user, generate a signalthat is interpreted by the control logic of the device 300 to be anactivation of a key, in this particular example. It will be recognizedthat touch sensors 324 may be any suitable sensor and may be located atany suitable location within the device as desired. The texture pockets322 may be, for example, thinned out sections that are molded into arear surface of the flexible skin structure 320. However, any suitableconfiguration may be used. In this example, the flexible skin structure320 includes a layer of flexible material that have a plurality ofdefined changeable skin texture elements 322, each having a portionconfigured to engage with the movable ramp structure 306. The capacitivesensor serves as a type touch sensor 324.

FIG. 4 illustrates an alternative embodiment to the single plate shownin FIG. 3. In this example, a multiple segment movable ramp structure308 includes a plurality of ramps 402, 404, 406 and a cam structure 408that mechanically engages with, for example, edges of the plurality oframps to move at least one of the plurality of ramps in response to, inone example, mechanical movement of a portion of the device. Forexample, if the device has a clam type housing design, movement of theclam housing causes rotation of the rotating cam 408 through a suitablemechanical linkage. Alternatively, a motor may be controlled to actuatethe movement of the plurality of ramps 402, 404, 406 directly orindirectly through rotating the cam 408. For example, a motor may becoupled to rotate the cam 408 based on an electrical control signal fromcontrol logic.

As shown, the ramp structure 308 includes a plurality of individualsliding ramp elements 402, 404 and 406 each including a plurality oframps 310. As also shown, the cam structure 408 which is shown to movein a rotational manner, may also be structured to move in anon-rotational manner, such as a sliding manner if desired, or any othersuitable manner. The cam structure includes ramp control elements 410that, in this example, protrude from the cam structure to engage an edgeof each of the respective individual sliding ramp elements 402, 404 and406. The ramp control elements 410 are positioned to cause movement ofthe plurality of sliding ramp elements in response to movement of thecam structure 408. Actuation of the plurality of sliding ramp elements402-406 may be done in response to the information set forth above suchas based on a received wireless signal, battery level change condition,such as a recharge condition (actuate skin), low battery level(deactuate skin), an incoming call, or based on any other suitablecondition. As such, a series of individual sliding panels are locatedbeneath a flexible skin structure 320 and are actuated in this exampleby a cam structure. The pattern of ramp control elements 410 determinein what sequence the sliding panels are actuated. As noted, the camstructure can be driven by a motor or integrated into the device suchthat a hinge of a clam shell type device that may be found, for example,on a mobile handset may actuate the cam directly so that opening of theclam shell causes the raising of the portions of the flexible skintexture to represent a keypad. It will also be recognized that themechanical actuation structure described may move any portion of theflexible skin structure 320 to provide, for example, raised portionsthat are not associated with a user interface and may be moved toprovide any desired tactile configuration.

FIG. 5 shows a cross sectional view of a controllable skin texturesurface 500 similar to that shown in FIG. 4 but in this example, theflexible skin structure 320 may also include tabs 502 that areintegrally formed with the texture pockets 322 to assist in raising thecenter of the texture pockets 322, if desired. As also shown, theflexible skin structure 320 is also considered to include a platestructure 504 that includes openings 506 corresponding to each desiredtexture element. The openings 506 receive the tabs 502 configured toengage with the movable ramp structure 308. As shown, as the movableramp structure 308 is moved, it raises or lowers portions of theflexible skin structure 320 in response to movement of the cam structure408. In this example, the individual sliding elements 402 and 406 havebeen moved to raise portions of the flexible skin structure 320 whereasindividual sliding element 404 has not been moved and therefore theflexible skin structure is flat at the appropriate locations. Aspreviously noted above, if the device includes a movable housing portionsuch as a clam shell configuration or any other suitable configuration,the movable housing portion may be mechanically coupled to the camstructure 408 such that mechanical movement of the housing portioncauses movement of the cam structure. Alternatively, the cam structuremay be electronically controlled independent of any movable housingportion as desired. For example, a motor may be coupled to engage withthe cam structure and move the cam structure in response to anelectronic control signal to move one or more of the plurality of rampsto a desired location.

As described, the sliding movable ramp structure 308, 404-406 with wedgeshaped features (e.g., ramps) moves horizontally to force tabs (e.g.,pins) molded into the back of the flexible skin structure upwardly andthereby causes portions of the flexible skin structure corresponding tothe texture pockets to be raised and thereby create a desired texturepattern. As noted above, a touch sensor, such as a capacitive sensor,may also be used to detect the touch of a user's finger against theflexible skin structure. The sensing may be used as an input to actuatethe texture mechanism or to execute another function that wouldcorrespond to the press of a button. In addition, mechanical switchessuch as dome-type switches known in the art could be placed underneathportions of the movable ramp structure to allow a user to press andthereby actuate one or more of the switches.

FIGS. 6 and 7 illustrate another example of a mechanical actuationstructure that uses a movable ramp structure and flexible skinstructure. In this example, the tabs 502 (FIG. 5) need not be utilized.Instead, a wedge shaped element 600 includes an anchored portion 602 anda movable wedge section 604 that pivots with respect to the anchoredportion 602. Each wedge shaped element 600 that includes the anchoredportion 602 and movable wedge section 604 may be secured in the devicein a fixed location below the flexible skin structure 320 and above asliding ramp or movable ramp structure 606. As the movable rampstructure 606 is moved horizontally, the pivotable wedge shaped elements604 are moved by ramp sections 608 of the movable ramp structure 606such that they come in contact with desired portions of the flexibleskin structure 320. Among other advantages, this structure may providereduced friction and wear between sliding elements and tabs molded intothe flexible skin structure. Other advantages may be recognized by thoseof ordinary skill in the art. However, any desired flexible skinstructure and ramp structure may be employed. Movement of the rampstructure causes movement of the wedge shaped elements and movement ofthe flexible skin structure to provide a change in tactileconfiguration. As also shown, the substrate anchored portion 602 servesas a substrate for the flexible skin structure 320 and is interposedbetween the flexible skin structure 320 and the movable ramp structure606. A touch sensor 324 is supported by the substrate and locatedbetween at least two movable portions (e.g., 322) of the flexible skinstructure. It will be recognized that the touch sensors 324 may besuitably located at any location depending upon the desiredfunctionality of the portable electronic device.

FIGS. 8, 9 and 10 illustrate an example of a shape memory alloyactuation structure 800 and a corresponding flexible skin structure 320that moves in response to movement of a metal alloy 812 in the shapememory alloy actuation structure 800 in accordance with one embodiment.FIG. 8 is a top view illustrating a plurality of pivoting elements802-808 that are pivotally connected with a base 810. The plurality ofpivoting elements 802-808 pivot along pivot points generally indicatedat 814 caused by, in this example, the lengthening and shortening of ashape memory alloy 812 such as nitinol wire, or any other suitable shapememory alloy. In one example, a single segment of shape memory alloy 812may be connected to the pivoting elements 802-808 and to the baseportion as diagrammatically illustrated as connection points 816. Itwill be recognized, however, that any suitable connection location orconnection technique may be used to affix one or more shape memory alloysegments to one or more pivoting elements. It will also be recognizedthat the shape of the pivoting elements and their length and materialmay vary depending upon the particular application. One example forillustration purposes only, and not limitation, may include usingpolypropylene or nylon. Also the hinged area or pivot location 814 maybe thinned if desired.

As shown, a voltage or current source 820 is selectively applied byopening and closing switch 822 by suitable control logic 200. Inaddition to, or alternatively, a separate segment of shape memory alloymay be used independently for each pivot element 802-808 so that eachpivot element may be controlled independently by the control logic.However, for purposes of explanation, the discussion will assume that asingle shape memory alloy element is used to move all the pivotingelements 802-808 at the same time. In any embodiment, when current ispassed through the shape memory alloy, it shortens, causing the pivotalelements 802-808 to push up against the flexible skin. As such, the base810 may be suitably mounted horizontally, for example, underneath theflexible skin structure and positioned so that the pivoting elements802-808 suitably align with desired portions of the flexible skinstructure to move (e.g., raise and lower) portions of the flexible skinstructure. As noted, different or separate wires may be attached todifferent pivoting elements in order to provide selectively as to whichtexture elements are actuated. In this example, the controllable skintexture surface includes a skin texture actuation structure thatincludes a plurality of pivoting elements 802-808 having a shape memoryalloy (whether single or multiple elements thereof) coupled to the skintexture to effect movement of the pivoting elements against the flexibleskin structure which moves in response to movement of the plurality ofpivoting elements. The movement of the pivoting elements change atactile configuration of a portion of the controllable skin texturesurface that is contacted by the pivoting elements. The control logic200 activates, for example, switch 822 or a plurality of other switchesto provide suitable current to control movement of the pivoting elementsby applying current to the shape memory alloy element 812. If desired, avoltage source or current source may be provided for each individualpivoting element and may be selectively switched in/out to control themovement of each pivoting element as desired. Any other suitableconfiguration may be also be employed. Also, the flexible skin over thehinged elements will generally act to provide a restorative force thatreturns the elements to a planar state when the current through the SMAis turned off.

FIGS. 9 and 10 show a cross section of one pivoting element of FIG. 8and further includes the illustration of the flexible skin structure 320and further shows a pivoting element 808 in both an activated state(FIG. 10) where the flexible skin structure is raised, and an inactivestate where the flexible skin structure 320 is flat (FIG. 9). As such inthis example, the flexible skin structure 320 has pockets correspondingto desired texture features that are molded into the reverse surface orunder surface thereof and bonded to a portion of the housing or othersubstructure within the device as noted above. A series of pivotingelements 802-808 underneath the flexible skin structure are connected,in one example, via a single length of shape memory alloy such that in aneutral position, the pivoting elements lie flat. When an electriccurrent is run through the shape memory alloy, its length shortens by,for example, approximately 5% or any other length depending upon thetype of shape memory alloy, and causes the pivoting elements to rise upand push against the flexible skin structure causing the appearance of abump. When the electrical current is no longer applied, the flexibleskin structure and underlying pivoting element returns to the neutralposition due to tension in the flexible skin.

In another embodiment shown in FIG. 10 b, a second series of pivotingelements 1002, as part of a hinge lock structure, may be introducedbeneath the first series of pivotal elements 806, 808 to act as locks.When the first series of hinged elements 806, 808 are actuated, thesecond series of pivoting elements 1002 are positioned so as to fall into gaps 1000 created by the motion of the first set of pivoting elementsthereby locking them into the raised position or to simply positionunderneath the first pivotal elements. It will be recognized that anyother location may also be used or that any other suitable technique maybe employed. When the electric current applied to the correspondingshape memory alloy element 812 that moves the first set of hingedelements 808 is stopped, the locking action of the second set ofelements 1002 holds the first pivoting elements 806, 808 in place by abiasing element 1006 pulling the elements 1002 under the elements 808.By applying an electric current to a shape memory alloy element 1004connected to the second set of pivoting elements 1002, the first set ofpivoting elements 806, 808 will be unlocked and thereby allows the firstseries of pivoting elements to return to a neutral position due totension in the flexible skin. This provides a type of bi-stable shapememory alloy actuation scheme. As shown, an end of a biasing element1006 such as a spring is fixedly attached to a portion of the housing orany other suitable structure and another end is caused to contact aportion of the pivotal second set of elements 1002. The pivotal secondset of elements may be made of any suitable structure such as plasticthat suitably bends about a pivot point shown as 1008. As shown, aportion of the pivoting elements 1002 are also fixedly attached to astructure of the device to prevent movement of an end thereof.Similarly, the shape memory alloy element 1004 associated with eachlocking element 1002 also has a portion connected to the element 1002 aswell as a fixed structure. The locking element swings as shown, in thisexample in plane of the FIG. 10 b, for example, to block the hingedelement 808 from lowering down into the plane of the page as shown. Assuch, the locking feature moves in the plane of the surface to lock thehinged elements. This as opposed to, for example, moving out of theplane in an opposite direction of the hinged element, which may also bedone if desired. The thickness of the overall implementation, however,may be less if the locking element is caused to move in plane to thefigure as shown. In this example, the hinged elements 808 rise out ofthe plane when actuated by an SMA element or actuator (not shown) and isblocked by the locking element moving in plane of the figure as shown.It will be recognized that although a single locking element 1002 isshown, that a suitable array of locking elements may be positioned forany respective pivoting hinged element 808. In addition, it will berecognized that in this example, a configuration as shown that providesa passive lock and an active unlock condition. However, it will berecognized that by reversing the bias element and the shape memory alloyelement 1006 and 1004 respectively, that an active lock and a passiveunlock structure may be employed. Hence, one or more pivoting elementsserves as a type of pivot lock structure made of a shape memory alloy,the same type for example, as noted above. The pivot lock structure iscoupled to the control logic 200 and is controlled to be positioned tolock the pivoting elements in a desired position. The pivot lockstructure may be alternately positioned to passively lock the pivotingelements in a desired position, and then controlled to release them whendesired. As such the control logic controls the second shape memoryalloy to deactuate the hinge lock structure to unlock the plurality ofhinged elements in response to a passive actuation of the hinge lockstructure.

A method for actuating a controllable skin texture surface includes, forexample, controlling the first shape memory alloy to actuate theplurality of pivoting elements. In response to the actuation, the pivotlock structure will naturally act to lock the plurality of pivotingelements in a first position. The method includes deactivating the firstshape memory alloy in response to the pivot lock structure beingactuated. This allows the current to the first pivoting element to beremoved and it is locked in place. The method may also include thenunlocking the hinged elements by, for example, by actuating the firstshape memory alloy and then controlling the second shape memory alloy tounlock the hinge lock structure by applying current to the shape memoryalloy actuator that moves the lock structure to unlock the pivotingelements from their raised position.

FIG. 11 illustrates a portion of a portable electronic device thatemploys an embodiment of a controllable skin texture surface, and inthis example, the portion of the electronic device is shown to be akeypad. In this example, the controllable skin texture surface includesa skin texture surface actuation structure that includes a hydraulicactuation structure that causes a change in tactile configuration of aflexible skin structure in response to movement of fluid underneath theflexible skin structure. FIGS. 12 and 13 are cross sectional views of aportion of FIG. 11 and will be described together with FIG. 11. Aflexible skin structure 1100 similar to that described above withrespect, for example, to FIG. 3 and elsewhere, includes fluid chambersor pockets 1102 corresponding to desired texture features that aremolded into a reverse surface of the flexible skin structure. As alsoshown above, the wall thickness of the pockets may be thinner than otherportions of the flexible skin texture to allow less resistance to fluidexpansion. The flexible skin structure 1100 is bonded, for example, to asurface of the housing of the portable electronic device to formsuitable seals around the various fluid chambers 1102. A supportingsubstrate 1104 which may be the housing of the device or a separatesubstrate within the device, includes fluid channels 1106 formed thereinthat are positioned to be in fluid communication with the fluid chambers1102. It will be recognized that any suitable structure of firstchannels 1106 may be used including separate channels that allow theactivation of any suitable texture location, depending upon the desiredapplication.

As shown in FIGS. 12 and 13 for example, when fluid is removed from thechannels 1106, the flexible skin structure 1100 is flat or in anunactuated state, and when an appropriate amount of fluid is moved intothe various chambers, the flexible skin structure is actuated atappropriate locations to provide a three dimensional pattern on an outersurface of the portable electronic device. As shown, the channels 1106are fluidly connected with one or more manifolds 1108 that may be moldedinto a surface of the housing or substrate 1104 or be a separatestructure if desired. Separate positive displacement pumps (not shown)or one pump may be fluidly coupled to an inlet 1110 in each of themanifolds. The manifolds 1108 as described are in fluid communicationwith one or more fluid reservoirs via one or more pumps. Control logic200 sends the appropriate control information to cause the positivedisplacement pumps to transfer fluid from an internal reservoir (notshown) in the device through the manifold and into the channels andhence the chambers molded into the rear surface of the flexible skinstructure 1100. The hydraulic actuation structure includes in thisexample, the substrate 1104 that includes one or more fluid channels1106 and the flexible skin structure 1100 is suitably affixed to thesubstrate either directly or through any suitable intermediatestructures. The flexible skin structure 1100 includes a plurality offluid pockets also shown as 1102 corresponding to texture features. Thefluid pockets 1102 are in fluid communication with the fluid channels1106 to allow fluid to be added to or removed from the chamber toactuate or deactuate the respective texture feature.

In one example, as noted above, fluid pumps may be controlled viacontrol logic. In another embodiment, the pumps may be activated viamechanical movement of a movable portion of the housing, such as amovement of a clam shell such that, for example, the rotational movementof a housing portion causes the fluid to be pumped into the fluidchambers. In one example, the pump is controlled to reverse fluid flowwhen the flip portion is closed. As such, there may be a fluid pumpoperative to move fluid into the fluid passages (and out of thepassages) and a movable housing portion that is coupled with the fluidpump such that mechanical movement of the housing portion causes thefluid pump to pump fluid in at least one fluid passage. The movement ofthe movable housing portion in another direction may serve to removefluid from the one or more respective chambers and return it to aninternal reservoir.

FIG. 14 illustrates another embodiment of a hydraulic actuationstructure and flexible skin structure that in this example, shows fluidchannels 1400 with additional fluid channels 1402 connected withspecific chambers that are molded into a rear surface of the flexibleskin structure 1100. The flexible skin structure includes multiplefeatures wherein movement of each of the features is controlledindependently. The fluid channels 1400 are in fluid communication withthe manifold 1404 whereas other chambers 1401 are in fluid communicationwith manifold 1406. As also shown, suitable pump inlets 1408 and 1410are shown that are in fluid communication with pumps (not shown). Inaddition, light sources 1412 and 1414 are positioned in proximity to therespective manifold 1404 and 1406 to serve as a light source (such asone or more colored LEDs) and a clear fluid may be used to act as alight guide to direct the light from the internal light sources to, forexample, translucent flexible portions of the flexible skin structure.Alternatively, the fluid itself may be colored so as to make the raisedtexture elements visually distinct by the change in color due to thecolor fluid contained therein. Any other suitable combination may alsobe employed if desired. The light sources may be suitably controlled toturn on and off as desired based on an incoming call, user programmedsequence, be activated by a ring tone, or may be controlled in any othersuitable manner by the control logic.

FIG. 15 illustrates one example of the portable electronic device 1500with the appearance of a 3D pattern with five tactile surfaces beingactuated. Unactuated portions 1502 are shown to be flat in thisparticular example.

FIG. 16 illustrates an alternative embodiment wherein the flexible skinstructure 1600 includes molded pocket patterns 1602 in an under portionthereof to receive fluid. A rigid substrate 1604 includes the suitablypositioned fluid channels 1606 that are in fluid communication with oneor more manifolds 1608 and also include a pump inlet. The manifold 1608is attached to a rear side of the right substrate 1604 and is in fluidcommunication with channels 1606 through openings 1610. Each of themicrochannels include, for example, openings 1610 to allow fluid to passfrom the manifold into the channel 1606 as described above. One or morepumps may also be used as noted above to raise and lower the pattern1602 by passing fluid in or out of the channel 1606. As such, in thisexample, if the pattern 1602 is placed, for example, on the back of acell phone or on the face of a cell phone, the outer skin of the cellphone may be activated to give a three dimensional texture that may besuitably activated and deactivated as desired. The channels 1606 may bepositioned with sufficiently fine spacing that they provide any suitabletexture pattern to be actuated. It will also be recognized that the skintexture may have one or more cover layers to protect the skin texturefrom damage from ultraviolet radiation, physical scratches, or any otherpotential hazards.

FIG. 17 is a block diagram illustrating one example of the structure1700 for controlling the hydraulic controllable skin texture surfaceexamples noted above. The device may include one or more fluid pumps1702 which provide fluid 1704 to and from the controllable skin texturesurface. Control logic, in one example, shown as 200 provides suitablecontrol information 1708 in the form of analog or digital signals, forexample, to control the one or more fluid pumps 1702 to provide thefluid 1704 in a controlled manner to actuate and deactuate one or moreportions of a flexible skin to provide a three dimensional tactileconfiguration as desired. It will also be recognized that instead of afluid, a pressurized gas could be employed.

FIGS. 18 a and 18 b illustrate another embodiment wherein, instead of asliding ramp structure (for example as shown in FIGS. 6 and 7), aplurality of hinged elements 1830 that have an anchored portion 1832attached to the flexible skin structure 320 through a suitable adhesiveor through any other suitable attachment mechanism. Each of the hingedelements 1830 also have a movable section 1834. The flexible skinstructure 320 includes pins 1836 which are, for example, longer thanthose shown in FIG. 6.

The device further includes a substrate 1840 such as, for example, aprinted circuit board which has attached thereto, dome switches 1842 asknown in the art. The dome switches 1842 are positioned to align underthe pins. A flexible sliding member 1846 is interposed between thesubstrate 1840 and the anchored portion 1832 underneath the flexibleskin surface 320. The flexible sliding member 1846 may be made from, forexample, nylon or polypropylene sheet, or other suitably flexiblematerial that allows motion of the movable section of the hinged element1834 to be transferred to the dome switch 1842. Holes 1850 in theflexible sliding member 1846 allow the movable sections of hingedelements 1834 to rotate downward toward the substrate 1840, as shown inFIG. 18 a. It can be seen that when the flexible sliding member 1846 isin the position shown in FIG. 18 a, the end of the movable section ofthe hinged element 1834 may be designed so as to come in contact withthe substrate 1840 such that pressing the flexible surface 320 will notactuate the dome switch 1842.

As shown in FIG. 18 b, the flexible sliding member 1846 is moved, asdescribed above based on any suitable structure to activate and in thiscase, raise portions of the flexible skin structure 320. However, sincethe material is compressible, when a user presses on a top surface ofthe flexible skin structure 320, the pin causes the moving portion 1834to press down upon the flexible material of the flexible sliding member1846 and depress the dome switch 1842. As such, in this embodiment, auser may activate the dome switch only when the flexible skin texture isactuated. It will be recognized that the geometry of the movable sectionof the hinged element 1834 may also be designed such that the domeswitch may be actuated by pressing the flexible skin 320 whether theskin is in either the actuated or unactuated state (FIGS. 18 b and 18 a,respectively). Among other advantages, this embodiment may allow theflexible sliding member 1846 to be stamped rather than, for example,molded and also uses conventional dome switches in combination therebyproviding a potentially lower cost structure. The hinged elements 1830may be made of any suitable material such as nylon, polypropylene sheetor any other suitable material as desired. As also noted above, theflexible sliding member may be configured as a sliding member thatslides along rails formed in a housing or other structure or may beconfigured in any other suitable manner as desired.

FIGS. 19-20 illustrate another example of a controllable skin texturesurface structure that employs an expandable gas actuation structure toraise and lower desired portions of a flexible skin structure to providea controllable tactile surface of a portable electronic device. As shownin FIG. 18, a skin texture surface actuation structure includes anexpandable gas actuation structure that includes a gas therein 1802 suchas air, or a material such as Freon or alcohol that changes from liquidto gas at a specified temperature and pressure, and a flexible skinstructure 1804 such as the type described above. The expandable gasactuation structure includes a gas chamber 1800 that is thermallycoupled to a heating element 1808 such as an electrical resistor, or anyother suitable structure, that may be turned on and off by control logicas desired to heat the gas 1802 within the chamber 1800 and cause thegas to expand. The expansion of the gas 1802 causes the gas to expandand fill the chamber 1800 of the flexible skin structure 1804. When theheating element 1808 is turned off, the gas cools and the chamber 1800collapses to put the flexible skin structure in an unactuated state. Assuch, the flexible skin structure 1804, as also described above,includes pockets corresponding to desired texture features wherein thepockets or chambers are molded into the reverse surface or anundersurface of the flexible skin structure 1804. The flexible skinstructure 1804 is attached to a substrate 1814 as described above, whichmay be part of the housing of the device or any other structure. It isbonded so as to provide a sealed environment so that the gas 1802 in thechamber 1800 cannot escape the chamber 1800. When an electric current issent through the heating element 1808, the increased temperature causesthe trapped gas in the pockets to expand thereby raising the pocket orouter surface over the chamber 1810. The flexible skin structureincludes expandable portions (e.g., pockets) that define a plurality ofgas chambers. Each of the gas chambers includes a controllable heatingelement that may be activated together or individually.

The substrate 1814 includes a heating element(s) 1808 corresponding toeach respective texture element. In addition, as noted above, all of theexamples described herein may include one or more touch sensors 202which may be used in any suitable manner. FIG. 19 shows a deactivatedstate of the flexible skin texture and FIG. 20 shows an activated stateof the flexible skin structure 1804.

FIGS. 21 and 22 diagrammatically illustrate one example of acontrollable skin texture surface 2102 with a particular pattern 2102that may be activated and nonactivated using one or more of the abovedescribed actuation structures based on any suitable condition. In thisexample, the tactile configuration or pattern 2102 may simply be locatedon an outer surface of the portable electronic device 2106 and need notbe part of a user interface but instead provides a unique visualexperience and tactile experience for a user.

FIGS. 23-25 illustrate yet another example of controlling of acontrollable skin texture surface 2300 (here shown as multiple hearts)of the types described above wherein a different portion 2302-2306 isactivated at different points in time by control logic to give a visualappearance or tactile feel of a moving object. In this example, a“heart” in the pattern is activated at different times. Also, animationof texture, such as variations in surface texture over time, may be usedto animate a character or feature. It will be recognized that the abovedescription and examples are merely for illustrative purposes only andthat any suitable configurations, designs or structures may be employedas desired.

Among other advantages, a portable electronic device includescontrollable skin texture surfaces to provide unique user experiences byproviding different tactile configurations (and/or visual appearances)by selectively controlling portions of a flexible skin structure usingvarious skin texture surface actuation structures. Also, all of thecontrollable skin texture surface configurations herein can be employedin the handheld wireless device shown in FIG. 1 or any suitable device.Other advantages will be recognized by those of ordinary skill in theart.

The above detailed description of the invention, and the examplesdescribed therein, has been presented for the purposes of illustrationand description. While the principles of the invention have beendescribed above in connection with a specific device, it is to beclearly understood that this description is made only by way of exampleand not as a limitation on the scope of the invention.

1. A portable electronic device comprising: a controllable skin texturesurface comprising a skin texture surface actuation structure that iscomprised of a plurality of hinged elements having a first shape memoryalloy coupled thereto to effect movement of the hinged elements and aflexible skin structure that moves in response to movement of theplurality of hinged elements to change a tactile configuration of atleast a portion of the controllable skin texture surface.
 2. Theportable electronic device of claim 1 comprising control logicoperatively coupled to the shape memory alloy to control movement of thehinged elements.
 3. The portable electronic device of claim 2 whereinthe control logic is operative to control the controllable skin texturesurface to change the tactile configuration of a non-user interfaceportion of the portable electronic device.
 4. The portable electronicdevice of claim 2 wherein the control logic is operative to control thecontrollable skin texture surface to change the tactile configuration ofa user interface key of the portable electronic device.
 5. The portableelectronic device of claim 2 comprising a hinge lock structurecomprising a second shape memory alloy, operatively coupled to thecontrol logic and positioned to controllably lock the hinged elements ina desired position.
 6. The portable electronic device of claim 5 whereinthe control logic is operative to: control the first shape memory alloyto actuate the plurality of hinged elements; in response, control thesecond shape memory alloy to actuate the hinge lock structure to lockthe plurality of hinged elements in a first position; deactivate thefirst shape memory alloy in response to the hinge lock structure beingactuated; and unlock the plurality of hinged elements by actuating thefirst shape memory alloy and thereby allow the hinge lock to disengage.7. The portable electronic device of claim 5 wherein the first andsecond shape memory alloys are comprised of nitinol wire.
 8. Theportable electronic device of claim 5 wherein the control logic isoperative to: control the second shape memory alloy to deactuate thehinge lock structure to unlock the plurality of hinged elements inresponse to a passive actuation of the hinge lock structure.
 9. Ahandheld wireless device comprising: a wireless telephone subsystem; adisplay operatively coupled to the wireless telephone subsystem; and acontrollable skin texture surface comprising: a skin texture surfaceactuation structure that is comprised of a plurality of hinged elementshaving a first shape memory alloy coupled thereto to effect movement ofthe hinged elements; and a flexible skin structure that moves inresponse to movement of the plurality of hinged elements to change atactile configuration of at least a portion of the controllable skintexture surface.
 10. The handheld wireless device of claim 9 comprisingcontrol logic operatively coupled to the shape memory alloy to controlmovement of the hinged elements.
 11. The handheld wireless device ofclaim 10 wherein the control logic is operative to control thecontrollable skin texture surface to change the tactile configuration ofa non-user interface portion of the portable electronic device.
 12. Theportable electronic device of claim 10 wherein the control logic isoperative to control the controllable skin texture surface to change thetactile configuration of a user interface key of the portable electronicdevice.
 13. The portable electronic device of claim 10 comprising ahinge lock structure comprising a second shape memory alloy, operativelycoupled to the control logic and positioned to controllably lock thehinged elements in a desired position.
 14. The portable electronicdevice of claim 13 wherein the control logic is operative to: controlthe first shape memory alloy to actuate the plurality of hingedelements; in response, control the second shape memory alloy to actuatethe hinge lock structure to lock the plurality of hinged elements in afirst position; deactivate the first shape memory alloy in response tothe hinge lock structure being actuated; and unlock the plurality ofhinged elements by actuating the first shape memory alloy and therebyallow the hinge lock to disengage.
 15. The portable electronic device ofclaim 13 wherein the first and second shape memory alloys are comprisedof nitinol wire.
 16. A method comprising: controlling a first shapememory alloy to actuate a plurality of hinged elements; in response,controlling a second shape memory alloy to actuate a hinge lockstructure to lock the plurality of hinged elements in a first position;deactivating the first shape memory alloy in response to the hinge lockstructure being actuated; and unlock the plurality of hinged elements byactuating the first shape memory alloy and thereby allow the hinge lockto disengage.